To many people, antimatter probably sounds a lot stranger than it really is. before to answer the question in the headline let me quickly say what antimatter is and does.
In it’s most basic sense, antimatter is just matter with its electrical charge reversed. When antimatter comes into contact with matter, the result is: annihilation. Then the mass of the particle and its antiparticle are converted into a flash of pure energy. So it’s tempting to say that large-scale annihilation of antimatter and matter could theoretically be used in a destructive way. It seems really simple. Introduce antimatter to matter and wait for the “BOOM” (of course, with your hands over your ears and your goggles secured firmly to your face…safety first!). In the Star Trek episode “Obsession” they say that 30g of antimatter reacting with matter is enough to blow up half the atmosphere of an Earth-sized planet, which is truly spectacular, isn’t it? Well… that’s a nice entertainment, indeed; I also like Star Trek movie and some others like it such as Star Wars or Superman, I am always having fun watching these movies.
But now back to the question in the headline, is building an antimatter bomb realistically viable?
The short and straight forward definitive answer, is: NO.
ANTIMATTER BOMB – FACT OR FICTION?
Of course it’s a fiction, and so it will remain forever. But, now let me put more context here.
Unfortunately people in general are easy to deceive. This is sad but true, most people are naive. With a convincing enough comunicated narative, people believe what they are told and I am generally refering to what most politicians use to communicate, particulalry a lot on nonsense and lip service. Many such situations have already happen during the years and no doubt it will continue to happen in the future. Concerning antimatter the most notable case was about 20 years ago (particuarly in march 2004) when there was a spate of news reports claiming the U.S. Air Force to be developing antimatter weapons.
The stories seem to have grown out of a speech given on 24 March 2004 by a guy named Kenneth Edwards, at the time director of the “revolutionary munitions” team at the Munitions Directorate at Eglin Air Force Base in Florida. He was a keynote speaker at the NASA Institute for Advanced Concepts (NIAC) conference in Arlington, Virginia. And in that talk, Edwards discussed the potential uses of positrons-basic particles of antimatter. There is no doubt that Edwards was fully aware of and impressed by the potential of antimatter. His speech, which almost defied belief according to some media reports, stressed that “even specks of antimatter too small to see could be devastating”. This guy probably watched too many times StarTrek as he was absolutelly convinced that he knows what is he talking about. As an example he said that 50-millionths of a gram of positrons would be enough to generate a blast equal to the explosion (roughly 1800kg of TNT, according to the FBI) at the Alfred P. Murrah Federal Building in Oklahoma City in 1995, which killed 168 people and injured over 500.
Readers of the newspaper reports at the time in 2004 were reminded that these weapon systems ‘are “devastating” and that “the level of destruction is unimaginable“; he went further by suggesting that there is no “will be” or “could”, only “are” and “is“, as if these devices are already being developed. In his speech, the antimatter weapons were presented as “environmentally friendly”, in contrast to regular nuclear bombs, positron bombs “won’t eject plumes of radioactive debris”, and the primary product of the annihilation of positrons and electrons was advertised as an invisible but extremely dangerous burst of gamma radiation, which “can kill a large number of soldiers without touching the civilian population”. When journalists from the San Francisco Chronicle started asking questions, the Air Force allegedly forbade its employees from publicly discussing the antimatter research program. For conspiracy theorists this is the proof that the stories are true; that antimatter weapons of devastating power are in hand (metaphorically at least!).
What is the reality behind these claims? Are they feasible in principle let alone in practice? Is there any more to this than claims that Saddam Hussein was developing cold fusion weapons at the time of the first Gulf War? What therefore are we to make of the speech by Kenneth Edwards in 2004 that excited interest in the US Air Force’s research into antimatter weapons?
Well…It’s not a secret anymore that The U.S. Air Force and other arms of the U.S. government do have a reputation on multiple occasions for researching bizarre ideas in the hope that “if it is possible, then let it be us that do it“. That’s exactly what happened in the antimatter case as well. I am not getting political now and this is something I will never do, for many reasons for me politics is something that we can definitelly live without. Instead I am materials science engineer, I love what I do and I know something more about materials than most politicians or military heads are aware of. Seeing what they chatter and do, I don’t have any serios reason to wish to become one of them. So let me say it very loud and clear:
There is no way that antimatter could be created in sufficient quantities to be used in a bomb.
This is for the same reason as you cannot use it to store energy: we can’t accumulate enough of it at high enough density. Nor could it be transported, as the antimatter traps capable of containing any significant quantity of antimatter would have to be enormous, and would require huge amounts of energy to operate.
Besides, an antimatter bomb isn’t as spectacular as science fiction stories makes it seem, as I’ve mentioned earlier in StarTrek episode. If you add up all the antimatter made in more than 30 years of antimatter physics done at CERN labs at Geneva in Switzerland, and if you were very generous, you might get 10 billionths of a gram. Even if that exploded on your fingertip it would be no more dangerous than lighting a match. For comparison, 0,5kg of antimatter is equivalent to around 19 kilotons of TNT, so yes, antimatter would be stronger than any other explosives, but not quite as catastrophic as some sources indicate. Even if it were possible to produce antimatter at a faster rate, the cost would be enormous. 1 gram of antimatter would cost approximately a million billion dollars. Hence, thanks to the inefficiency of the transformation process of energy into antimatter, we do not have to worry about military applications. How do I know this so sure? Well… it’s not complicated to figure it out. You just need to recall the basic stuff you learned about matter in secondary school.
THE COST OF ANTIMATTER
As an example, let’s take a hypothetical 1 gram of antimatter, this is known to be the amount whose annihilation would release as much energy as a small atomic bomb. Now let’s do some basic arithmetic, 3 situation must be taken into consideration:
1st: How does antimatter equate with the Hiroshima bomb analogy: does a gram really measure up to a 20 kiloton bomb? – In fact, it is even more! A ‘kiloton of TNT’ corresponds to 4 million million (4.2 x 1012) joules (4 “TeraJoules’). A joule is a measure of energy, proportional to mass and to the square of speed; one joule is the kinetic energy of two kilograms moving at a speed of one metre per second, as non-relativistically kinetic energy = 1/2 mv². 1g is one thousandth of a kilogram: 10-3 kg, The speed of light is 300,000 km/s or 3 x 108 metres/s. Now the energy of this is E=mc², so for 1 gram we get E = 10-3 x 9 x 1016 kgm²/s² giving a total of 9 x 1013 joules or 90 TeraJoules’. As 4.2 TeraJoules corresponds to a kiloton of TNT, then 90 Terajoules corresponds to 21.4 kiloton. That is the energy trapped within a gram of antimatter.
This same amount is also trapped within a gram of matter, so we need only make half a gram of antimatter in order to be equally destructive as the Hiroshima bomb. This assumes however that you could liberate all of the energy at once. It is possible that after all the trouble and expense of making and storing it, the annihilation atom by atom might fizzle rather than explode.
2nd: How long would it take to make a gram, or even a nanogram (ngm), a billionth of a gram? – To make a gram of antiprotons you will need 6*1023 of them, while a gram of positrons would require 1026. The most intense source of antiprotons in the world is at Fermiab, in Winfield Township–Illinois U.S.A. As far as I know their record production over a month in June 2007 produced 1014 antiprotons. Were they able to do this every month for a year, they could produce about 1015, which equates to 1.5 billionths of a gram, or nanograms. Were we able to retain all of these antiprotons and annihilate them with 1.5 nanograms of matter, the total energy released would be about 270 Joules, which is like 5 seconds illumination by a feeble light bulb. The CERN AD produces on average about 40,000 antiprotons each second, or about 1013 in a year. This is only 1% of what Fermilab makes. However the purpose is different and those at CERN are colder, custom made for trapping and then capturing positrons in order to make atoms of antihydrogen.
It is possible that the production rate could eventually be increased by a factor of ten or, in extreme, a hundred, but even then the world antiproton production would still only be 3 nanograms. Take all of the antiprotons ever produced in history and the lightbulb could burn for a few minutes. Even this is unrealistic as these antiprotons were lost long ago, the numbers of antiprotons that have been stored is trifling compared with this. A physics facility at Darmstadt in Germany in the next few years might match Fermilab’s production. But even after adding all of these together the total world production falls far short of the optimistic hopes expressed by those promoting antiprotons for space fuel. As for antihydrogen, antiprotons trapped with positrons at CERN can make several hundred atoms of antihydrogen per second. With present technology, it would be possible to produce about a nanogram (billionth of a gram) of antimatter per year, at a cost of about tens of millions of dollars. To fill a toy balloon, let alone make a gram obviously, it would take hundreds of millions of years-and in excess of US$ 1,000 trillion – to make one gram. This appears ambitious even for the U.S. military.
3rd: How to contain the produced antimatter? – Let’s imagine a situation where antimatter was free and abundant. In addition to the cost and problems of making the stuff, storing it causes further difficulties. As I have said, ‘like charges repel’, so in order to contain the electric charge in a gram of pure antiprotons or of positrons, you would have to build a force field so powerful that were you to disrupt it, the explosive force as the charged particles flew apart would exceed anything that would have resulted from their annihilation. If it shifts the wrong way, if it isn’t contained by the magnets and kept stable, the antimatter will come in contact with the sides of the container and will annihilate…well, whoever happens to be carrying it at the time. If you want to make bombs, then it seems to me that it would be better to forget the antimatter and instead exploit the power behind the technology that you would need to contain it; besides you don’t need to go to the trouble, cost, and sheer impracticability of making antimatter as well.
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Following K. Edwards’ speech newspaper reporters contacted Eglin Air Force Base, whose response was initially very positive. In July 2004 Rex Swenson at Eglin’s Munitions Directorate confirmed that everyone was ‘very excited about this technology. Swenson was set to arrange media interviews with Edwards but within a month he was overruled by higher officials in the Air Force and Pentagon. According to the report in the San Francisco Chronicle, Edwards repeatedly declined to be interviewed claiming to be “under strict instructions” from his superiors. The tell-tale quote in the official line was that “we’re not at the point where we need to be doing any public interviews”. In the world of conspiracy theorists, this is ‘proof’ that the military are trying to suppress news of the latest big thing. In reality the explanation turns out to be much simpler: there were no antimatter weapons; the project was a dream. This whole thing about “military working on the antimatter bomb” was a veritable fraud.
The US Air Force was not developing antimatter weapons, Edwards’ 2004 talk notwithstanding. It had however funded a small research project into antiprotons, without any secrecy, at Pennsylvania State University and so the Positronics Research Center in Santa Fe-New Mexico. As the name implies, the emphasis has shifted from antiprotons to positrons, which are much more accessible. Advertised applications include energy storage, destruction of chemical and biological agents, nuclear medicine, and propulsion. But even so, there has been no demonstration or even serious claim that production or storage of bulk antimatter is achievable, not even in amounts that are the merest trifles of what would be required for energy.
Ironically, as it was already confirmed in case of the Atomic Bomb dropped at Hiroshima in 1945, the scientists realized the atom bomb to be a real possibility many years before one was actually built and exploded; the public then was totally surprised and amazed. The antimatter bomb on the other hand has been imagined by the public who wants to know more about it, yet we have known for a very long time that it’s not at all a practical device.
Computer Aided Design & The 118 Elements 
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